Last I'll just speculate on the TBA advanced weapons. I would submit the following:
Revolver:
d4 P
20 ft.
Reload 3
Bulk 1
Hands 1Fatal d8
Versatile B
Magazine 6Clean and simple; it just uses the flintlock pistol stats but comes with the opportunity to fire several shots in a burst before reloading. Less accurate than a dueling pistol due to the advanced category, and it doesn't fit in many builds because of how many feats affect reload 1 weapons, but in my experience that is where advanced weapons shine.
Honestly, that looks a bit underpowered to me. I'd suggest upping the base damage die to d6 leaving the fatal at d8 (to account for likely lower caliber bullets but with more stable damage to account for jacketed rounds working better with rifling) and setting the range increment to 30ft. Add the rare tag since these are likely only commonly available in Alkenstar, if you like.
While this is undeniably better than the martial counterpart, you have to take into account that you're giving a lot up in exchange for using an advanced weapon. You either have -2 to hit or spend a feat to take the Gunslinger equivalent of the fighter's Advanced Weapon Training. Every fourth round or so, you spend the entire
round reloading. This is likely even worse for the dual wield pistol builds. Beyond that, as you state yourself, you are giving up some of the benefits of reload 1 feats for what equates to 2 shots per reload action if a combat goes beyond 3 rounds.